Processing method, method of manufacturing semiconductor device, processing apparatus, and program product

Abstract

The invention relates to a processing method, a method of manufacturing a semiconductor device, a processing apparatus, and a program product. The present invention addresses the problem of providing a technique capable of efficiently etching an oxide film on a substrate surface. (a) a step for preparing a substrate having, on the surface thereof, an oxide film and a nitrogen-containing film formed so as to be thicker than the originally required thickness (T1) by a thickness (T2); and (b) a step in which a fluorine-containing substance is supplied to the substrate, and the oxide film on the surface of the substrate is etched using a substance (X) generated by a chemical reaction between the nitrogen-containing film and the fluorine-containing substance.

Description

Technical Field

[0001] This invention relates to processing methods, methods for manufacturing semiconductor devices, processing apparatus, and process articles. Background Technology

[0002] As a step in the semiconductor device manufacturing process, etching of the oxide film on the substrate surface is sometimes performed (see, for example, Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2023-137735 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] This invention provides a technique for efficiently etching oxide films on substrate surfaces.

[0008] Methods for solving problems

[0009] According to one aspect of the present invention, a technology is provided, comprising:

[0010] (a) A process of preparing a substrate, wherein the substrate has an oxide film on its surface and a nitrogen-containing film formed in such a way that it is thicker than the originally required thickness T1 by a thickness T2;

[0011] (b) A process of etching the oxide film on the surface of the substrate by supplying a fluorine-containing substance to the substrate and using a substance X generated by chemically reacting the nitrogen-containing film with the fluorine-containing substance.

[0012] Invention Effects

[0013] According to the present invention, etching of oxide films on substrate surfaces can be performed efficiently. Attached Figure Description

[0014] Figure 1 This is a schematic configuration diagram of a vertical processing furnace of a processing apparatus that can be suitably used in one aspect of the present invention, showing the portion of the processing furnace 202 in a longitudinal cross-sectional view.

[0015] Figure 2 This is a schematic diagram of a vertical processing furnace of a processing apparatus suitable for use in one aspect of the invention. Figure 1 The AA-line cross-sectional view shows part of the processing furnace 202.

[0016] Figure 3This is a schematic configuration diagram of the controller 121 of a processing device that can be suitably used in one aspect of the invention, and a block diagram showing the control system of the controller 121.

[0017] Figure 4 (a) is a partial cross-sectional enlarged view of the surface portion of the substrate in one embodiment of the present invention, showing a laminated film having a first nitrogen (N) film and a second nitrogen (N) film on the surface, and an oxide film formed on the substrate; Figure 4 (b) in the middle shows the... Figure 4 A partial cross-sectional magnified view of the surface portion of the substrate in one embodiment of the present invention, after the fluorine (F)-containing substance is supplied from state (a) to cause the surface of the second N-containing film to react chemically with the F-containing substance to generate reaction products; Figure 4 (c) in the diagram shows the result from... Figure 4 From state (b) in the present invention, under the condition of continued supply of F-containing substance, a partial cross-sectional magnified view of the surface portion of the substrate after the reaction product is decomposed to generate substance X, in one embodiment of the present invention. Figure 4 (d) in the text indicates that from Figure 4 From state (c) in the present invention, a partial cross-sectional magnified view of the surface portion of the substrate after etching a portion of the surface side of the oxide film using substance X while continuing to supply F-containing substance. Figure 4 (e) in the text indicates that from Figure 4 A partial cross-sectional enlarged view of the surface portion of the substrate in one embodiment of the present invention, after the F-containing substance is continuously supplied from state (d) to remove the second N-containing film and the oxide film respectively and expose the surfaces of the first N-containing film and the substrate respectively. Figure 4 (f) in the diagram shows the result from... Figure 4 A partial cross-sectional magnified view of the surface portion of the substrate in one embodiment of the present invention, after the formation of the film on the respective surfaces of the first N-containing film and the substrate, starting from state (e).

[0018] Figure 5 (a) is a partial cross-sectional enlarged view of a surface portion of a substrate in a modified example of one embodiment of the present invention, having a first N-containing film on the surface and an oxide film formed on the substrate; Figure 5 (b) in the middle shows the... Figure 5 A partial cross-sectional magnified view of the surface portion of the substrate in a modified example of one embodiment of the present invention, after the inhibitor has been adsorbed onto the surface of the oxide film, starting from state (a) in the diagram. Figure 5 (c) in the diagram shows the result from... Figure 5 A partial cross-sectional magnified view of the surface portion of the substrate in a modified example of one aspect of the present invention, starting from state (b) in the first N-containing film after the second N-containing film is formed on the first N-containing film; Figure 5(d) in the text indicates that from Figure 5 From state (c) onwards, a partial cross-sectional magnified view of the surface portion of the substrate in a modified example of one embodiment of the present invention after the inhibitor remaining on the surface of the oxide film has been removed.

[0019] Figure 6 (a) is a partial cross-sectional enlarged view of a surface portion of a substrate in a modified example of one embodiment of the invention, where an oxide film is formed on the surface of the substrate. Figure 6 (b) in the middle shows the... Figure 6 A partial cross-sectional magnified view of the surface portion of the substrate in a modified example of one embodiment of the present invention, after the inhibitor has been adsorbed onto the surface of the oxide film, starting from state (a) in the diagram. Figure 6 (c) in the diagram shows the result from... Figure 6 From state (b) in the diagram, a partial cross-sectional magnified view of the surface portion of the substrate in a modified example of one aspect of the present invention after a stacked film containing a first N-film and a second N-film has been formed on the surface; Figure 6 (d) in the text indicates that from Figure 6 From state (c) onwards, a partial cross-sectional magnified view of the surface portion of the substrate in a modified example of one embodiment of the present invention after the inhibitor remaining on the surface of the oxide film has been removed.

[0020] Figure 7 (a) is a partial cross-sectional enlarged view of a surface portion of a substrate in another embodiment of the invention having a first substrate and a second substrate on its surface, an oxide film formed on the surface of the first substrate, and an N-containing film formed on the surface of the second substrate. Figure 7 (b) in the middle shows the... Figure 7 A partial cross-sectional magnified view of the surface portion of the substrate in other embodiments of the present invention, after the F-containing substance is supplied from state (a) to the N-containing film surface and the F-containing substance react chemically to generate reaction products; Figure 7 (c) in the diagram shows the result from... Figure 7 From state (b) in the present invention, under the condition of continued supply of substance F, a partial cross-sectional magnified view of the surface portion of the substrate after the reaction product is decomposed to generate substance X, in another embodiment of the present invention. Figure 7 (d) in the text indicates that from Figure 7 From state (c) in the present invention, while continuing to supply F-containing material, a partial cross-sectional magnified view of the surface portion of the substrate after etching a portion of the surface side of the oxide film using material X, in another embodiment of the present invention. Figure 7 (e) in the text indicates that from Figure 7The partial cross-sectional magnified view of the surface portion of the substrate in another embodiment of the present invention after the supply of F-containing material continues from state (d) in the process of removing the N-containing film and the oxide film respectively, thereby exposing the respective surfaces of the second substrate and the first substrate; Figure 7 (f) in the diagram shows the result from... Figure 7 A partial cross-sectional magnified view of the surface portion of the substrate in another embodiment of the present invention after forming a film on the respective surfaces of the second and first substrates, starting from state (e).

[0021] Figure 8 (a) is a partial cross-sectional enlarged view of a surface portion of a substrate in another embodiment of the invention having a first substrate and a second substrate on its surface, with an oxide film formed on the surface of the first substrate; Figure 8 (b) in the middle shows the... Figure 8 A partial cross-sectional magnified view of the surface portion of the substrate in other embodiments of the present invention after the state (a) in which the inhibitor is adsorbed onto the surface of the oxide film; Figure 8 (c) in the diagram shows the result from... Figure 8 From state (b) in the diagram, a partial cross-sectional magnified view of the surface portion of the substrate in other embodiments of the present invention after the formation of the N-film on the surface of the second substrate; Figure 8 (d) in the text indicates that from Figure 8 From state (c) onwards, a partial cross-sectional magnified view of the surface portion of the substrate in another embodiment of the present invention after the inhibitor remaining on the surface of the oxide film has been removed.

[0022] Figure 9 This is a schematic diagram of a processing apparatus that can be suitably used in other aspects of the invention.

[0023] Figure 10 This is a schematic diagram of a processing apparatus that can be suitably used in other aspects of the invention.

[0024] Explanation of reference numerals in the attached figures

[0025] 200 wafers (substrates) Detailed Implementation

[0026] <One aspect of the invention>

[0027] The following is mainly based on Figures 1-3 , Figure 4 (a) in Figure 4 Section (f) describes one aspect of the invention. It should be noted that the drawings used in the following description are schematic, and the dimensional relationships and ratios of the elements shown in the drawings may not necessarily correspond to reality. Furthermore, the dimensional relationships and ratios of the elements may not be consistent between different drawings.

[0028] (1) Composition of the processing device

[0029] like Figure 1 As shown, the processing furnace 202 of the processing apparatus has a heater 207 that functions as a temperature regulator (heating unit). The heater 207 is cylindrical and is vertically mounted by being supported by a retaining plate. The heater 207 also functions as an activation mechanism (activation unit) that activates (excites) the gas by heat.

[0030] Inside the heater 207, a reaction tube 203 is arranged concentrically with the heater 207. The reaction tube 203 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC) and is formed into a cylindrical shape with a closed upper end and an open lower end. Below the reaction tube 203, a manifold 209 is arranged concentrically with the reaction tube 203. The manifold 209 is made of a metal material such as stainless steel (SUS) and is formed into a cylindrical shape with open upper and lower ends. The upper end of the manifold 209 engages with the lower end of the reaction tube 203 to support the reaction tube 203. An O-ring 220a is provided between the manifold 209 and the reaction tube 203 as a sealing component. The reaction tube 203 is installed vertically, just like the heater 207. The processing container (reaction container) is mainly composed of the reaction tube 203 and the manifold 209. A processing chamber 201 is formed in the hollow part of the processing container. The processing chamber 201 is configured to accommodate a wafer 200, which serves as a substrate. Processing of the wafer 200 is performed within the processing chamber 201.

[0031] Inside the processing chamber 201, nozzles 249a to 249c, serving as the first to third supply units, are respectively installed through the side wall of the manifold 209. These nozzles are also referred to as the first to the third nozzles. The nozzles 249a to 249c are made of heat-resistant materials such as quartz or SiC. Gas supply pipes 232a to 232c are connected to each of the nozzles 249a to 249c. The nozzles 249a to 249c are different nozzles, and each nozzle is adjacent to the nozzle 249b.

[0032] On gas supply pipes 232a to 232c, mass flow controllers (MFCs) 241a to 241c, serving as flow controllers (flow control units), and valves 243a to 243c, serving as on / off valves, are sequentially installed from the upstream side of the airflow. Gas supply pipes 232d and 232f are connected downstream of valve 243a on gas supply pipe 232a. Gas supply pipes 232e and 232g are connected downstream of valve 243b on gas supply pipe 232b. Gas supply pipe 232h is connected downstream of valve 243c on gas supply pipe 232c. On gas supply pipes 232d to 232h, MFCs 241d to 241h and valves 243d to 243h are sequentially installed from the upstream side of the airflow. Gas supply pipes 232a to 232h are constructed of, for example, a metal material such as SUS.

[0033] like Figure 2 As shown, nozzles 249a to 249c are respectively arranged upright above the wafer 200 in a ring-shaped space between the inner wall of the reaction tube 203 and the wafer 200, extending from the lower to the upper part of the inner wall of the reaction tube 203. That is, nozzles 249a to 249c are respectively arranged in a region horizontally surrounding the wafer arrangement area, along the wafer arrangement area for arranging the wafers 200. In top view, nozzle 249b is arranged so that the center of the wafer 200 within the processing chamber 201 is aligned with the exhaust port 231a (described later) in a straight line. Nozzles 249a and 249c are arranged to clamp a straight line L passing through the center of nozzle 249b and exhaust port 231a from both sides along the inner wall of the reaction tube 203 (the outer periphery of the wafer 200). Straight line L also passes through the center of nozzle 249b and wafer 200. That is, nozzle 249c can also be positioned on the opposite side of nozzle 249a, sandwiching a straight line L. Nozzles 249a and 249c are arranged linearly symmetrically about the straight line L. Gas supply holes 250a to 250c are respectively provided on the side of nozzles 249a to 249c. Gas supply holes 250a to 250c open in a manner that faces exhaust port 231a when viewed from above, and are configured to supply gas to wafer 200. Multiple gas supply holes 250a to 250c are provided from the bottom to the top of reaction tube 203.

[0034] Fluorine (F)-containing substances are supplied into the processing chamber 201 from the gas supply pipe 232a via MFC 241a, valve 243a, and nozzle 249a.

[0035] The first raw material and the second raw material are supplied into the processing chamber 201 through the gas supply pipe 232b via MFC 241b, valve 243b, and nozzle 249b. The first raw material is used as one of the first film-forming agents. The second raw material is used as one of the second film-forming agents.

[0036] The dopant is supplied into the processing chamber 201 from the gas supply pipe 232c via MFC 241c, valve 243c, and nozzle 249c. The dopant is used as one of the first film-forming agents.

[0037] Modifier is supplied to the processing chamber 201 from gas supply pipe 232d via MFC 241d, valve 243d, gas supply pipe 232a, and nozzle 249a.

[0038] The reactant and the remover are supplied into the treatment chamber 201 through gas supply pipe 232e, MFC 241e, valve 243e, gas supply pipe 232b, and nozzle 249b. The reactant is used as one of the second film-forming agents.

[0039] Inactive gases are supplied to the treatment chamber 201 through gas supply pipes 232f-232h via MFCs 241f-241h, valves 243f-243h, gas supply pipes 232a-232c, and nozzles 249a-249c. These inactive gases function as purge gas, carrier gas, and dilution gas.

[0040] The system mainly consists of gas supply pipe 232a, MFC 241a, and valve 243a, forming the F-containing substance supply system. The system mainly consists of gas supply pipe 232b, MFC 241b, and valve 243b, forming the first and second raw material supply systems. The system mainly consists of gas supply pipe 232c, MFC 241c, and valve 243c, forming the dopant supply system. The system mainly consists of gas supply pipe 232d, MFC 241d, and valve 243d, forming the modifier supply system. The system mainly consists of gas supply pipe 232e, MFC 241e, and valve 243e, forming the reactant and remover supply systems. The system mainly consists of gas supply pipes 232f-232h, MFC 241f-241h, and valves 243f-243h, forming the inactive gas supply system. The first raw material supply system and the dopant supply system, or all of them, are referred to as the first film-forming agent supply system. The second raw material supply system and the reactant supply system, or all of them, are referred to as the second film-forming agent supply system.

[0041] Any or all of the aforementioned supply systems can also be configured as an integrated supply system 248, incorporating valves 243a-243h, MFCs 241a-241h, etc. The integrated supply system 248 is configured to connect to gas supply pipes 232a-232h, and the supply of various substances (various gases) into these pipes, i.e., the opening and closing of valves 243a-243h, and the flow regulation of MFCs 241a-241h, are controlled by the controller 121 described later. The integrated supply system 248 can be configured as a single or separate integrated unit, allowing for assembly and disassembly of the gas supply pipes 232a-232h, etc., and enabling maintenance, replacement, and addition of the integrated supply system 248 on a unit-by-unit basis.

[0042] An exhaust port 231a is provided below the side wall of the reaction tube 203 to exhaust the atmosphere inside the processing chamber 201. For example... Figure 2 As shown, the exhaust port 231a is positioned opposite (facing) the nozzles 249a-249c (gas supply holes 250a-250c) when viewed from above, with the wafer 200 clamped in place. The exhaust port 231a can also be positioned along the side wall of the reaction tube 203 from bottom to top, i.e., along the wafer arrangement area. An exhaust pipe 231 is connected to the exhaust port 231a. A vacuum pump 246, serving as a vacuum exhaust device, is connected to the exhaust pipe 231 via a pressure sensor 245 (which detects the pressure inside the processing chamber 201) and an APC (Auto Pressure Controller) valve 244 (which acts as a pressure regulator). The APC valve 244 is configured to allow for vacuum exhaust and cessation of vacuum exhaust within the processing chamber 201 by opening and closing the valve while the vacuum pump 246 is operating. Furthermore, while the vacuum pump 246 is operating, the pressure within the processing chamber 201 can be adjusted by regulating the valve opening based on pressure information detected by the pressure sensor 245. The exhaust system mainly consists of the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. The vacuum pump 246 may also be included in the exhaust system.

[0043] Below the manifold 209, a sealing cover 219, serving as a furnace opening cover, is provided to airtightly seal the lower opening of the manifold 209. The sealing cover 219 is made of a metal material such as SUS and is formed in a disc shape. An O-ring 220b, serving as a sealing member, is provided on the upper surface of the sealing cover 219 and abuts against the lower end of the manifold 209. Below the sealing cover 219, a rotation mechanism 267 is provided to rotate the crystal boat 217 (described later). The rotation shaft 255 of the rotation mechanism 267 passes through the sealing cover 219 and is connected to the crystal boat 217. The rotation mechanism 267 is configured to rotate the wafer 200 by rotating the crystal boat 217. The sealing cover 219 is configured to move vertically via a crystal boat lift 115, which is a lifting mechanism located outside the reaction tube 203. The crystal boat lift 115 is configured as a conveying device (transfer mechanism) that moves the wafer 200 into and out of the processing chamber 201 by raising and lowering the sealing cover 219, and functions as a device (preparation device) for preparing the substrate in the processing container. It should be noted that, as in the modified example described later, when the substrate to be processed is made in the processing chamber 201, that is, when a predetermined film is formed on the surface of the substrate in the processing chamber 201 to make the substrate to be processed, the various parts of the processing apparatus for film formation (modifier supply system, second film-forming agent supply system, remover supply system, etc.) and the crystal boat lift 115 function as a preparation device.

[0044] Below the manifold 209, a gate 219s, serving as a furnace opening cover, is provided. This gate can airtightly seal the lower opening of the manifold 209 when the sealing cover 219 is lowered and the crystal boat 217 is removed from the processing chamber 201. The gate 219s is made of a metal material such as SUS and is formed in a disc shape. An O-ring 220c, serving as a sealing component, is provided on the upper surface of the gate 219s, abutting against the lower end of the manifold 209. The opening and closing actions (lifting, rotating, etc.) of the gate 219s are controlled by a gate opening and closing mechanism 115s.

[0045] The crystal boat 217, serving as a substrate support, is configured to support multiple wafers 200, for example, 25 to 200 wafers, arranged horizontally and aligned centrally in a vertical direction, in multiple layers, even if they are spaced apart. The crystal boat 217 is made of heat-resistant materials such as quartz or SiC. A heat-insulating plate 218, made of heat-resistant materials such as quartz or SiC, is supported in multiple layers at the bottom of the crystal boat 217. The crystal boat 217 can also be considered part of the aforementioned preparation apparatus.

[0046] A temperature sensor 263, serving as a temperature detector, is installed inside the reaction tube 203. By adjusting the energizing state of the heater 207 based on the temperature information detected by the temperature sensor 263, the temperature within the processing chamber 201 is adjusted to achieve the desired temperature distribution. The temperature sensor 263 is disposed along the inner wall of the reaction tube 203.

[0047] like Figure 3 As shown, the controller 121, serving as the control unit (control unit), is configured as a computer equipped with a CPU (Central Processing Unit) 121a, RAM (Random Access Memory) 121b, storage device 121c, and I / O port 121d. The RAM 121b, storage device 121c, and I / O port 121d are configured to exchange data with the CPU 121a via an internal bus 121e. An input / output device 122, such as a touch panel, is connected to the controller 121. Furthermore, an external storage device 123 can be connected to the controller 121. It should be noted that the processing device can be configured to have one control unit or multiple control units. That is, one control unit can be used to control the processing sequence described later, or multiple control units can be used to control the processing sequence described later. Furthermore, multiple control units can be configured as a control system interconnected via a wired or wireless communication network, or the entire control system can control the processing sequence described later. When the term "control unit" is used in this specification, in addition to the case of having one control unit, there are also cases of having multiple control units and cases of having a control system composed of multiple control units.

[0048] Storage device 121c is configured such as flash memory, HDD (Hard Disk Drive), SSD (Solid State Drive), etc. Storage device 121c contains, in a readable manner, a control program that controls the operation of the processing device, and a process flow that describes the steps and conditions of the substrate processing described later. The process flow is formed by the controller 121 causing the processing device to execute each step of the substrate processing described later, and combining them in a way that yields a predetermined result, thus functioning as a program. Hereinafter, process flow, control program, etc., are collectively referred to as a program (program workpiece). Additionally, process flow is also referred to simply as a process. When the term "program" is used in this specification, there may be cases where only the process flow is included, cases where only the control program is included, or cases where both are included. RAM 121b is configured as a memory area (working area) that temporarily holds the program, data, etc., read by CPU 121a.

[0049] I / O port 121d is connected to the aforementioned MFC241a~241h, valves 243a~243h, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotating mechanism 267, crystal boat elevator 115, gate opening and closing mechanism 115s, etc.

[0050] CPU 121a is configured to read and execute control programs from storage device 121c, and to read processes from storage device 121c based on inputs such as operation commands from input / output device 122. CPU 121a is configured to control, in accordance with the read process content, the flow regulation of various substances (various gases) based on MFC 241a to 241h, the opening and closing of valves 243a to 243h, the opening and closing of APC valve 244, the pressure regulation based on pressure sensor 245 and using APC valve 244, the start and stop of vacuum pump 246, the temperature regulation of heater 207 based on temperature sensor 263, the rotation and rotation speed regulation of crystal boat 217 based on rotation mechanism 267, the lifting and lowering of crystal boat 217 based on crystal boat elevator 115, and the opening and closing of gate 219s based on gate opening and closing mechanism 115s.

[0051] The controller 121 can be configured by installing the aforementioned program, recorded and stored in the external storage device 123, into a computer. The external storage device 123 includes, for example, a hard disk such as an HDD, an optical disk such as a CD, a USB flash drive, or a semiconductor memory such as an SSD. The storage device 121c and the external storage device 123 constitute a computer-readable recording medium. Hereinafter, they will be collectively referred to simply as recording media. When the term "recording medium" is used in this specification, there may be a case where only the storage device 121c is included, a case where only the external storage device 123 is included, or a case where both are included. It should be noted that the external storage device 123 may also be omitted, and the program may be provided to the computer using a communication unit such as the Internet or a dedicated line.

[0052] (2) Processing procedures

[0053] Main use Figure 4 (a) in Figure 4Section (f) illustrates an example of a method for processing a substrate using the aforementioned processing apparatus as a step in a semiconductor device manufacturing process (manufacturing method). Specifically, it describes an example of a processing sequence in which a process for etching the surface of the wafer 200, which serves as the substrate, and a process for growing a film on the etched wafer 200 are performed consecutively. In the following description, the operation of each component of the processing apparatus is controlled by the controller 121. It should be noted that the processing apparatus is also referred to as a substrate processing apparatus. Furthermore, the processing method is also referred to as a substrate processing method.

[0054] In the processing order of this method, the following steps are performed:

[0055] (a) Step A of preparing wafer 200, which has an oxide film on its surface and a nitrogen (N) film formed in such a way that it is thicker than the originally required thickness T1 by a thickness T2.

[0056] (b) Step B, which involves supplying an F-containing substance to the wafer 200 and using a substance X generated by chemically reacting an N-containing film with the F-containing substance to etch the oxide film on the surface of the wafer 200.

[0057] It should be noted that the following examples are explained in relation to the following situations:

[0058] After step B, proceed further.

[0059] (c) Step C, which involves supplying a first film-forming agent to the wafer 200 to form a film on the surface of the wafer 200 after the oxide film has been etched.

[0060] The term "wafer" as used in this specification can refer to the wafer itself, or to a laminate of a wafer and a specified layer or film formed on its surface. The term "surface of the wafer" as used in this specification can refer to the surface of the wafer itself, or to the surface of a specified film, etc., formed on the wafer. When described in this specification as "forming a specified film on the wafer," it can mean forming the specified film directly on the surface of the wafer itself, or forming the specified film on top of a film, etc., formed on the wafer. The term "substrate" as used in this specification is also synonymous with the term "wafer."

[0061] The terms "agent" and "substance" as used in this specification include at least one of gaseous and liquid substances. Liquid substances include mist substances. That is, the F-containing substance, modifier, remover, first film-forming agent (first raw material, dopant), and second film-forming agent (second raw material, reactant) may each contain gaseous substances, mist substances, or other liquid substances, or both.

[0062] (Step A)

[0063] First, multiple wafers 200 are loaded into the (wafer-filling) crystal boat 217.

[0064] As described above, an oxide film and an N-containing film are pre-formed on the surface of the wafer 200, with the oxide film being thicker than the originally required thickness T1 by a thickness T2. Figure 4 As shown in (a), the N-containing film on the surface of wafer 200 includes a stacked film of a first N-containing film of thickness T1 and a second N-containing film of thickness T2.

[0065] As described later, in step B, the oxide film is etched and removed. However, at this time, the portion of the upper layer with thickness T2 of the N-containing film is removed, leaving the portion of the lower layer with thickness T1 remaining. The first N-containing film corresponds to the portion of the lower layer with thickness T1 in the N-containing film, and is the necessary film in the N-containing film, that is, the film that needs to remain on the wafer 200 without reducing its thickness from T1 in step B. In addition, the second N-containing film corresponds to the portion of the upper layer with thickness T2 in the N-containing film, and is the redundant (unnecessary) film in the N-containing film, that is, the film that needs to be removed from the wafer 200 in step B. It should be noted that the thickness T2 is a thickness that allows the N-containing film to be removed in step B.

[0066] In this specification, the necessary membrane in the N-containing film, namely the portion of thickness T1 on the lower layer side, i.e., the first N-containing film of thickness T1, is simply referred to as the first N-containing film. Furthermore, the excess membrane in the N-containing film, namely the portion of thickness T2 on the upper layer side, i.e., the second N-containing film of thickness T2, is simply referred to as the second N-containing film.

[0067] The first and second N-containing films sometimes comprise films containing silicon (Si), a semiconductor element, such as silicon nitride (SiN), silicon carbon nitride (SiCN), silicon oxynitride (SiON), silicon oxycarbon nitride (SiOCN), silicon boron carbon nitride (SiBCN), and silicon boron nitride (SiBN), etc., containing both Si and N. Alternatively, the first and second N-containing films sometimes comprise films containing titanium nitride (TiN), tungsten nitride (WN), and aluminum nitride (AlN), etc., containing both metal elements and N. It should be noted that the materials, composition, and constituent elements of these films can be the same or different. For example, the first N-containing film could be a SiN film, and the second N-containing film could also be a SiCN film, and the second N-containing film could be a SiN film.

[0068] Preferably, the first and second N-containing films are prepared in advance in such a way that the first N-containing film has higher etch resistance to F-containing substances than the second N-containing film. Furthermore, it is preferable that the first and second N-containing films are prepared in advance in such a way that at least the portion of the first N-containing film in contact with the second N-containing film has higher etch resistance to F-containing substances than the second N-containing film.

[0069] Oxide films sometimes include silicon oxide films (SiO films). Additionally, oxide films sometimes include silicon oxide films (SiO films) with non-stoichiometric compositions. x The oxide film (where x is a real number less than 2) and at least one of a silicon oxide film (SiO2 film) with a stoichiometric composition. Additionally, the oxide film sometimes includes at least one of a native oxide film and a chemically oxidized oxide film. It should be noted that SiO2 will also be referred to as such below. x The membrane and SiO2 membrane are collectively referred to as SiO membrane.

[0070] The substrate of the oxide film sometimes includes at least one of the following: a substrate containing semiconductor elements such as single-crystal Si; a film containing semiconductor elements such as silicon film (Si film), germanium film (Ge film), and silicon-germanium film (SiGe film); a film containing semiconductor elements and nitrogen such as SiN film, SiCN film, SiON film, SiOCN film, SiBCN film, and SiBN film; a film containing metal elements and nitrogen such as TiN film, WN film, and AlN film; a film containing semiconductor elements and oxygen such as SiO film and silicon oxide carbide film (SiOC film); a film containing metal elements and oxygen such as titanium oxide film (TiO film), hafnium oxide film (HfO film), zirconium oxide film (ZrO film), and aluminum oxide film (AlO film); and a film containing metal elements such as tungsten (W film), molybdenum film (Mo film), and ruthenium film (Ru film).

[0071] After the wafer filling is completed, the gate 219s is moved by the gate opening and closing mechanism 115s, opening the lower end of the manifold 209 (gate opening). Then, as... Figure 1 As shown, the crystal boat 217 supporting the wafer 200 is lifted by the crystal boat elevator 115 and moved into the processing chamber 201 (crystal boat loading). In this state, the sealing cover 219 seals the lower end of the manifold 209 via the O-ring 220b.

[0072] With the completion of the crystal boat loading, the following state is formed: the substrate to be processed, i.e., the wafer 200 having an oxide film on its surface and an N-film containing a film that is thicker than the originally required thickness T1 by a thickness T2, is prepared (configured) in the processing chamber 201.

[0073] (Pressure and temperature regulation)

[0074] After the crystal boat loading is completed, vacuum exhaust (pressure reduction exhaust) is performed by vacuum pump 246 to bring the pressure (vacuum level) inside processing chamber 201, i.e., the space where wafer 200 exists, to the desired level. At this time, the pressure inside processing chamber 201 is measured by pressure sensor 245, and feedback control is applied to APC valve 244 based on this measured pressure information. Additionally, wafer 200 inside processing chamber 201 is heated by heater 207 to reach the desired processing temperature. At this time, feedback control is applied to the energizing status of heater 207 based on temperature information detected by temperature sensor 263 to achieve the desired temperature distribution inside processing chamber 201. Furthermore, rotation of wafer 200 is initiated based on rotation mechanism 267. Exhausting from processing chamber 201, heating wafer 200, and rotation all continue at least until the processing of wafer 200 is completed.

[0075] (Step B)

[0076] Then, F-containing material is supplied to the wafer 200 in the processing chamber 201.

[0077] Specifically, valve 243a is opened to allow the F-containing substance to flow into the gas supply pipe 232a. The F-containing substance is regulated by MFC 241a and supplied into the processing chamber 201 via nozzle 249a, and exhausted from the exhaust port 231a. At this time, the F-containing substance is supplied to the wafer 200 from the side, exposing the wafer 200 to the F-containing substance (F-containing substance supply and exposure). At this time, valves 243f to 243h can also be opened to supply inactive gases into the processing chamber 201 via nozzles 249a to 249c, respectively.

[0078] By supplying an F-containing substance to the wafer 200 under the processing conditions described later, a portion of thickness T2 in the N-containing film, namely the second N-containing film, can chemically react with the F-containing substance to generate substance X. Substance X is generated during the etching of the second N-containing film by the F-containing substance. More specifically, substance X is generated by the decomposition of reaction products generated during the etching of the second N-containing film by the F-containing substance. Substance X contains nitrogen (N) and hydrogen (H). By generating substance X within the processing chamber 201 where the F-containing substance is supplied, the oxide film on the surface of the wafer 200 can be etched efficiently using substance X.

[0079] For example, if the oxide film on the surface of the wafer 200 includes a silicon oxide film (SiO2), the second N-containing film on the surface of the wafer 200 includes a silicon nitride film (Si3N4), and the F-containing substance supplied to the processing chamber 201 includes hydrogen fluoride (HF), the reaction shown in the following formula can be carried out under the conditions described later.

[0080] Si3N4 + 16HF → 3(NH4)2SiF6 + 2H2

[0081] (NH4)2SiF6→SiF4+2HF+2NH3

[0082] SiO2+4HF+4NH3→SiF4+2H2O+4NH3

[0083] That is, on the surface of the chip 200, such as Figure 4 As shown in (b), the second N-containing film (Si3N4) undergoes a chemical reaction with an F-containing substance (HF), for example, producing solid reaction products such as ammonium fluorosilicate, i.e., ammonium hexafluorosilicate ((NH4)2SiF6). Additionally, on the surface of the wafer 200, such as... Figure 4 As shown in (c), the solid reaction product is decomposed (thermal decomposition, etc.) to produce hydrogen nitride such as ammonia (NH3) as substance X. This is achieved by producing N- and H-containing substances such as NH3 in the presence of an F-containing substance (HF). Figure 4 As shown in (d), the etching reaction of the oxide film (SiO2) present on the surface of the wafer 200 can be promoted. In this step, by supplying the wafer 200 with an F-containing material, the second N-containing film and the oxide film can be etched in parallel, and these films can be gradually thinned. Furthermore, by continuing to supply the wafer 200 with an F-containing material, such as... Figure 4 As shown in (e), the second N-containing film and the oxide film can be removed separately, thereby exposing the surfaces of the first N-containing film and the substrate. That is, for the N-containing film, the portion of thickness T1 can be removed while the portion of thickness T2 remains. It should be noted that during the removal of the oxide film using F-containing substances and substance X, solid reaction products such as (NH4)2SiF6 may sometimes be generated again. However, in this reaction system, the solid reaction products are immediately decomposed after generation, and the above reactions will occur in a chain reaction. That is, in this reaction system, the chain reaction of reaction, generation of solid reaction products, decomposition of solid reaction products, and etching can suppress the solid reaction products from remaining as solid residues on the outermost surface of the oxide film to be etched.

[0084] According to the present invention, as described above, the etching reaction can be initiated without triggering the reaction between the F-containing substance (HF) and water (H2O). That is, according to the present invention, at the beginning of step B, the etching reaction can be initiated in the absence of H2O in the processing chamber 201, and the oxide film on the surface of the wafer 200 can be etched.

[0085] After removing the second nitrogen-containing film and the oxide film, valve 243a is closed to stop the supply of F-containing substances to the processing chamber 201. Then, a vacuum is applied to the processing chamber 201 to remove any remaining gaseous substances. At this time, valves 243f to 243h are opened, and inactive gases are supplied to the processing chamber 201 through nozzles 249a to 249c. The inactive gases supplied from nozzles 249a to 249c act as purge gases, thereby purging the processing chamber 201.

[0086] Examples of processing conditions for supplying substance F in step B include:

[0087] Processing temperature: room temperature (25℃) to 200℃, preferably 50℃ to 175℃, more preferably 100℃ to 150℃, and even more preferably 120℃ to 150℃.

[0088] Processing pressure: 10–3000 Pa, preferably 10–2000 Pa

[0089] Processing time: 1–120 minutes, preferably 1–100 minutes

[0090] Supply flow rate of F-containing substances: 0.5–3 slm, preferably 1–2 slm

[0091] Inactive gas supply flow rate (per gas supply tube): 0-10 slm, preferably 1-5 slm.

[0092] It should be noted that the numerical range "25~200℃" in this specification refers to the inclusion of both the lower and upper limits within that range. Therefore, for example, "25~200℃" means "above 25℃ and below 200℃". The same applies to other numerical ranges. Furthermore, the processing temperature in this specification refers to the temperature of the wafer 200 or the temperature inside the processing chamber 201, and the processing pressure refers to the pressure inside the processing chamber 201. Additionally, the processing time refers to the duration of the processing. Also, when the supply flow rate includes 0 slm, 0 slm means that the substance (gas) is not supplied. These same principles apply in the following descriptions.

[0093] Here, if the processing temperature when supplying the F-containing substance in step B is set to be below room temperature (25°C), the etching rate can be increased. However, if other processes such as film formation are performed before or after the etching process, the time for changing the processing temperature (heating time and / or cooling time) between the etching process and other processes sometimes becomes too long, resulting in reduced productivity.

[0094] By maintaining the processing temperature at room temperature (25°C) or higher, a high etching rate can be maintained, and the temperature change time between processing and other processes can be shortened, thus suppressing productivity loss. By maintaining the processing temperature at 50°C or higher, while maintaining a high etching rate, the temperature change time between processing and other processes can be further shortened, thus further suppressing productivity loss. By maintaining the processing temperature at 100°C or higher, while maintaining a high etching rate, the temperature change time between processing and other processes can be significantly shortened, thus significantly improving productivity. By maintaining the processing temperature at 120°C or higher, while maintaining a high etching rate, the temperature change time between processing and other processes can be further significantly shortened, thus further improving productivity.

[0095] In addition, if the processing temperature is set to a temperature higher than 200°C, although the time for changing the processing temperature between other processes can be greatly shortened, the etching rate becomes too low, and sometimes the productivity decreases.

[0096] By keeping the processing temperature below 200°C, the time required to change processing temperature with other processes can be significantly reduced, and the decrease in etching rate can be suppressed, thereby suppressing the decrease in productivity. By keeping the processing temperature below 175°C, the time required to change processing temperature with other processes can be significantly reduced, and the decrease in etching rate can be further suppressed, thereby further suppressing the decrease in productivity. By keeping the processing temperature below 150°C, the time required to change processing temperature with other processes can be significantly reduced, and the decrease in etching rate can be significantly suppressed, thereby significantly suppressing the decrease in productivity.

[0097] Based on the above, the processing temperature is above room temperature (25°C) and below 200°C, preferably above 50°C and below 175°C, more preferably above 100°C and below 150°C, and even more preferably above 120°C and below 150°C.

[0098] As a substance containing fluorine (F), a hydrogen (H)-containing substance such as hydrogen fluoride (HF) can be used. Other examples of substances containing fluorine (F₂), nitrogen trifluoride (NF₃), chlorine trifluoride (ClF₃), and chlorine fluoride (ClF) can also be used. One or more of these substances can be used as a substance containing fluorine (F).

[0099] As inert gases, rare gases such as nitrogen (N2), argon (Ar), helium (He), neon (Ne), and xenon (Xe) can be used. One or more of these can be used as inert gases. This principle also applies to the steps described later.

[0100] (Step C)

[0101] After step B is completed, the output of heater 207 is adjusted so that the temperature of wafer 200 reaches the specified processing temperature described later. Additionally, a first raw material, serving as the first film-forming agent, is supplied to wafer 200 within processing chamber 201.

[0102] Specifically, valve 243b is opened, allowing the first raw material to flow into the gas supply pipe 232b. The flow rate of the first raw material is regulated by MFC 241b, and it is supplied into the processing chamber 201 via nozzle 249b and exhausted from the exhaust port 231a. At this time, the first raw material is supplied to the wafer 200 from the side, exposing the wafer 200 to the first raw material (first raw material supply, exposure). At this time, valves 243f to 243h can also be opened to supply inactive gases into the processing chamber 201 via nozzles 249a to 249c, respectively.

[0103] By supplying the first material to the wafer 200 under the processing conditions described later, thereby achieving... Figure 4 As shown in (f), a predetermined film can be formed on the surface of the wafer 200 where the second N-containing film and oxide film have been removed, i.e., on the exposed surfaces of the first N-containing film and the substrate. When using the material described later as the first raw material, a Si film can be formed on the surface of the wafer 200.

[0104] After a predetermined film is formed on the surface of the wafer 200 where the second N-containing film and oxide film have been removed, valve 243b is closed to stop the supply of the first raw material into the processing chamber 201. Furthermore, the processing chamber 201 is purged using the same processing steps as in step B.

[0105] Examples of processing conditions for supplying the first raw material as the first film-forming agent in step C include:

[0106] Processing temperature: 500–650℃, preferably 550–600℃

[0107] Processing pressure: 4–200 Pa, preferably 1–120 Pa

[0108] Processing time: 10–120 minutes, preferably 20–60 minutes

[0109] The first raw material supply flow rate is 0.1–5 slm, preferably 0.2–3 slm.

[0110] Inactive gas supply flow rate (per gas supply tube): 0-10 slm, preferably 0.1-5 slm.

[0111] As the first raw material, silane (SiH4), silane (Si2H6), propane (Si3H8), and butane (Si4H) can be used, for example. 10 Hydrogenated silicon, etc.

[0112] (Post-purging and atmospheric pressure recovery)

[0113] After step C is completed, inert gases are supplied as purge gases into the processing chamber 201 from nozzles 249a to 249c, and exhaust gases are discharged from exhaust port 231a. This purges the processing chamber 201, removing residual gases and reaction byproducts (post-purge). Then, the atmosphere in the processing chamber 201 is replaced with an inert gas (inert gas replacement), and the pressure in the processing chamber 201 is restored to atmospheric pressure (atmospheric pressure restoration).

[0114] (Jingzhou Unloading)

[0115] Next, the sealing cover 219 is lowered using the crystal boat lift 115, opening the lower end of the manifold 209. Then, the processed wafer 200, supported by the crystal boat 217, is moved from the lower end of the manifold 209 (crystal boat unloading) to the outside of the reaction tube 203. After the crystal boat is unloaded, the gate 219s is moved, sealing the lower end opening of the manifold 209 through the O-ring 220c (gate closing). Then, the processed wafer 200 is removed from the crystal boat 217 (wafer removal).

[0116] The processing steps in one aspect of the present invention are now complete, as described above.

[0117] It should be noted that steps B and C above are preferably performed in the same processing chamber (in-situ). If a series of processes are performed in-situ, the wafer 200 will not be exposed to the atmosphere during the process, and stable processing can be consistently performed while the wafer 200 is under vacuum. Furthermore, in this method, an F-containing substance supply system, a first raw material supply system, and an inactive gas supply system are used; however, since a second raw material supply system, a dopant supply system, a modifier supply system, a reactant supply system, and a remover supply system are not used, these supply systems can be omitted.

[0118] (3) The effect of this method

[0119] According to this method, one or more of the following effects can be obtained.

[0120] (a) Step A is performed to prepare a substrate having an oxide film on its surface and an N-containing film formed in a manner that is thicker than the originally required thickness T1 by a thickness T2. Then, step B is performed to supply the substrate with an F-containing substance. Thus, the oxide film on the surface of the substrate can be etched using substance X, which is generated by chemically reacting the second N-containing film with the F-containing substance. The etching reaction of the oxide film is promoted by substance X, resulting in efficient etching.

[0121] Furthermore, by utilizing substance X, the processing temperature during etching of the oxide film can be increased to a higher temperature. Therefore, in at least one of the processes before or after etching, when performing other processes such as film formation, the processing temperature during etching can be made close to the processing temperature of the other processes. This shortens the time required to change the processing temperature between etching and other processes, i.e., it shortens at least one of the heating and cooling times, thereby increasing productivity.

[0122] Furthermore, by increasing the processing temperature during etching, the solid reaction products generated during the reaction can be decomposed and removed while an fluorine-containing substance is supplied. This prevents the solid reaction products generated during the reaction from remaining on the outermost surface of the oxide film to be etched, thus preventing further reaction. Additionally, after stopping the supply of the fluorine-containing substance, a separate process to raise the processing temperature and sublimate the solid reaction products is unnecessary, thereby increasing productivity.

[0123] Furthermore, when etching oxide films on the surfaces of multiple substrates, substance X can be generated on the surface of each substrate, which can improve the uniformity between substrates in the oxide film etching process.

[0124] Furthermore, since there is no need to set up a separate supply line for material X, the cost of the equipment can be reduced accordingly. Additionally, by omitting the supply line for material X, the supply system can be simplified, reducing labor and costs associated with its maintenance. Moreover, there is no need to place components (such as pseudo-wafers with N-film formed on their surfaces) near the substrate for in-situ generation of material X, nor is it necessary to reduce the number of substrates processed at one time. Consequently, any increase in processing costs can be avoided.

[0125] Furthermore, a first N-containing film and a second N-containing film are pre-formed on the surface of the substrate prepared in step A. This eliminates the need for a modifier supply system, a remover supply system, a reactant supply system, etc., thereby simplifying the supply system and reducing the labor and cost of maintaining it.

[0126] (b) The second N-containing film contains Si, and the F-containing substance contains H. Therefore, the aforementioned effects can be effectively obtained. Alternatively, the second N-containing film contains a SiN film, and the F-containing substance contains HF. Therefore, the aforementioned effects can be effectively obtained.

[0127] (c) Substance X contains N and H. Additionally, substance X is generated during the etching of the second N-containing film by the F-containing substance. Furthermore, substance X is generated by the decomposition of reaction products generated during the etching of the second N-containing film by the F-containing substance. The aforementioned effects can be effectively achieved through at least one of these methods.

[0128] (d) The oxide film comprises a SiO film. Additionally, the oxide film comprises at least one of a non-stoichiometric SiO film and a stoichiometric SiO film. Furthermore, the oxide film comprises at least one of a native oxide film and a chemically oxidized oxide film. The aforementioned effects can be effectively obtained through at least one of these methods.

[0129] (e) After step B, step C is performed. This reduces the impurity concentration (oxygen concentration, etc.) at the interface between the substrate and the film formed in step C.

[0130] (f) In the N-containing film, the first N-containing film exhibits higher etch resistance to the F-containing substance than the second N-containing film. Furthermore, in the N-containing film, at least the portion of the first N-containing film in contact with the second N-containing film exhibits higher etch resistance to the F-containing substance than the second N-containing film. Through at least one of these factors, in step B, over-etching of the N-containing film can be suppressed, and the portion of thickness T2 in the N-containing film can be removed with high precision, leaving the portion of thickness T1 remaining.

[0131] (g) When using any of the specified substances selected from the above-mentioned F-containing substances, the first film-forming agent (first raw material), and the various inactive gases, the above-mentioned effects can also be obtained.

[0132] (4) Variations

[0133] The processing order in this method can be changed as shown in the following variations. These variations can be combined arbitrarily. Unless otherwise specified, the processing steps and conditions in each step of each variation can be set to be the same as those in each step of the above processing order.

[0134] (Variation Example 1)

[0135] In step A, a second N-containing film of thickness T2 may also be formed on the first N-containing film of thickness T1 pre-formed on the surface of the wafer 200.

[0136] In this case, in step A, the following can be performed:

[0137] (a1) Step A1, in which a modifier is supplied to wafer 200, thereby causing the inhibitor contained in the modifier to be adsorbed on the surface of the oxide film;

[0138] (a2) Step A2, which forms a state in which an N-containing film comprising a stacked film is formed on the surface of the wafer 200 by supplying a second film-forming agent to the wafer 200 on which an inhibitor is adsorbed on the surface of the oxide film, wherein the stacked film is a stacked film of a first N-containing film of thickness T1 and a second N-containing film of thickness T2.

[0139] The following is mainly based on Figure 5 (a) in Figure 5 (d) in the text explains step A of this variation.

[0140] First, the wafer 200 to be processed is prepared in the processing chamber 201 through the same processing steps as described above for wafer filling and crystal boat loading. For example... Figure 5 As shown in (a) of this modified example, a first N-containing film and an oxide film of thickness T1 are pre-formed on the surface of the wafer 200. A second N-containing film is not formed on the first N-containing film. The surface of the first N-containing film is exposed.

[0141] (Step A1)

[0142] After the temperature and pressure are regulated in the processing chamber 201, a modifier is supplied to the wafer 200 in the processing chamber 201.

[0143] Specifically, valve 243d is opened, allowing the modifier to flow into the gas supply pipe 232d. The modifier's flow rate is regulated using MFC 241d, and it is supplied to the processing chamber 201 via gas supply pipe 232a and nozzle 249a, and exhausted from exhaust port 231a. At this time, the modifier is supplied to the wafer 200 from the side, exposing the wafer 200 to the modifier (modifier supply, exposure). Alternatively, valves 243f to 243h can be opened to supply inactive gases into the processing chamber 201 via nozzles 249a to 249c, respectively.

[0144] Under the processing conditions described later, by supplying a modifier to wafer 200, thereby achieving the desired effect... Figure 5 As shown in (b), the inhibitor contained in the modifier can be adsorbed onto the surface of the oxide film, selectively forming an inhibitor layer on the surface of the oxide film within the oxide film and the first N-containing film. The inhibitor contains at least a portion of the molecular structure constituting the molecule of the modifier, i.e., residues of the modifier contained in the modifier. The inhibitor layer is an aggregate of inhibitors, comprising a high-density layer densely covering the surface of the oxide film. The inhibitor layer functions in step A2 described later to inhibit or hinder (prevent) the film-forming reaction on the oxide film. The above-mentioned effect based on the inhibitor layer is also referred to as the inhibitor effect (film-forming inhibition effect, film-forming inhibition effect).

[0145] It should be noted that, in this invention, for example, the expression "selectively forming a layer on the first surface, among the first and second surfaces," refers to the relative degree to which the layer is formed on each surface. That is, this expression means that the layer is formed to a greater degree on the first surface than on the second surface. In other words, the expression "selective" in this invention means that the processing of other surfaces is prioritized relative to the processing of one surface. This is also true in the following description.

[0146] After an inhibitor layer is formed on the surface of the oxide film, valve 243d is closed to stop the supply of modifier to the treatment chamber 201. Then, the treatment chamber 201 is purged using the same treatment steps as in step B of the above-described method.

[0147] Examples of processing conditions for supplying the modifier in step A1 include:

[0148] Processing temperature: room temperature (25℃) to 500℃, preferably room temperature to 250℃.

[0149] Processing pressure: 1–2000 Pa, preferably 10–1000 Pa

[0150] Processing time: 1–3600 seconds, preferably 5–300 seconds

[0151] Modifier supply flow rate: 0.001–10 slm, preferably 0.1–0.5 slm

[0152] Inactive gas supply flow rate (per gas supply pipe): 0–20 slm.

[0153] As a modifier, an organic substance containing at least one of a hydrocarbon group and an amino group, and / or an inorganic substance containing a halogen can be used. It should be noted that when using both, it is preferable to first supply the organic substance, then purge, and then supply the inorganic substance. When using the substances exemplified below, the surface of the oxide film is capped by hydrocarbon groups such as alkyl groups, H, Cl, F, etc., and the alkyl ends, hydrocarbon ends, H ends, Cl ends, F ends, etc., function as inhibitors.

[0154] As a modifier, for example, (dipropylamino)trimethylsilane ((C3H7)2NSi(CH3)3), (dibutylamino)trimethylsilane ((C4H9)2NSi(CH3)3), (dimethylamino)trimethylsilane ((CH3)2NSi(CH3)3), (diethylamino)triethylsilane ((C2H5)2NSi(C2H5)3), (dimethylamino)triethylsilane ((CH3)2NSi(C2H5)3), (diethylamino)trimethylsilane ((C2H5 ...2NS 5) 2NSi(CH3)3), (trimethylsilyl)amine ((CH3)3SiNH2), (triethylsilyl)amine ((C2H5)3SiNH2), (dimethylamino)silane ((CH3)2NSiH3), (diethylamino)silane ((C2H5)2NSiH3), (dipropylamino)silane ((C3H7)2NSiH3), (dibutylamino)silane ((C4H9)2NSiH3), hydrogen chloride (HCl), chlorine (Cl2), ClF3, F2, etc. One or more of these can be used as modifiers.

[0155] (Step A2)

[0156] After step A1 is completed, the wafer 200 in the processing chamber 201 is supplied with a second raw material as a second film-forming agent in step A2a, and with reactants as a second film-forming agent in step A2b.

[0157] [Step A2a]

[0158] In this step, the second material is supplied to the wafer 200 in the processing chamber 201 through the same processing steps as in step C of the above method.

[0159] By supplying the second material to the wafer 200 under the processing conditions described later, it is possible to suppress the adsorption of at least a portion of the molecular structure constituting the second material onto the oxide film surface, and to promote the selective adsorption of at least a portion of the molecular structure constituting the second material onto the surface of the first N-containing film. Thus, a first layer formed by the adsorption of at least a portion of the molecular structure constituting the second material can be selectively (preferably) formed on the surface of the first N-containing film.

[0160] After the first layer is formed on the surface of the first N-containing film, the supply of the second raw material is stopped. Then, the treatment chamber 201 is purged using the same treatment steps as in step B of the above method.

[0161] As a second raw material, substances with chlorine (Cl) groups bonded to Si, such as monochlorosilane (SiH3Cl), dichlorosilane (SiH2Cl2), trichlorosilane (SiHCl3), tetrachlorosilane (SiCl4), hexachlorodisilane (Si2Cl6), and octachlorotrisilane (Si3Cl8), can be used. Alternatively, substances with hydrogen (H) and amino groups bonded to Si, such as tetra(dimethylamino)silane (Si[N(CH3)2]4), tris(dimethylamino)silane (Si[N(CH3)2]3H), and bis(diethylamino)silane (Si[N(C2H5)2]2H2), can be used. One or more of these can be used as the second raw material.

[0162] Examples of processing conditions for supplying the second raw material as the second film-forming agent in step A2a include:

[0163] Processing temperature: room temperature (25℃) to 700℃, preferably 350 to 550℃

[0164] Processing pressure: 1–2000 Pa, preferably 1–1333 Pa

[0165] Processing time: 1–180 seconds, preferably 10–120 seconds

[0166] The second raw material supply flow rate is 0.001–2 slm, preferably 0.01–1 slm.

[0167] Inactive gas supply flow rate (per gas supply tube): 0-10 slm, preferably 0.1-5 slm.

[0168] [Step A2b]

[0169] In this step, reactants are supplied to the wafer 200 inside the processing chamber 201.

[0170] Specifically, valve 243e is opened, allowing reactants to flow into gas supply pipe 232e. The flow rate of the reactants is regulated using MFC 241e, and they are supplied to processing chamber 201 via gas supply pipe 232b and nozzle 249b, and exhausted from exhaust port 231a. At this time, reactants are supplied to wafer 200 from the side, exposing wafer 200 to the reactants (reactant supply, exposure). Alternatively, valves 243f to 243h can be opened to supply inactive gases into processing chamber 201 via nozzles 249a to 249c, respectively.

[0171] By supplying reactants to the wafer 200 under the processing conditions described later, at least a portion of the first layer formed on the surface of the first N-containing film in step A2a can be converted (nitrided). Consequently, a second layer, formed by nitriding the first layer, is selectively (preferably) formed on the surface of the first N-containing film.

[0172] After the second layer is formed on the surface of the first N-containing film, valve 243e is closed to stop the supply of reactants to the processing chamber 201. Then, the processing chamber 201 is purged using the same processing steps as in step B of the above-described method.

[0173] As reactants, nitriding agents (nitriding gases) can be used, for example. As nitriding agents, substances containing N and H, such as ammonia (NH3), diazoxide (N2H2), hydrazine (N2H4), and N3H8, i.e., hydrogen nitride, can be used. One or more of these can be used as reactants.

[0174] Examples of processing conditions for supplying reactants as the second film-forming agent in step A2b include:

[0175] Processing pressure: 1–4000 Pa, preferably 1–1333 Pa

[0176] Reactant supply flow rate: 0.01–20 slm, preferably 0.01–10 slm.

[0177] Other processing conditions can be set to be the same as those in step A2a.

[0178] [Performed a specified number of times]

[0179] By performing the loop containing steps A2a and A2b a specified number of times (n times, where n is an integer of 1 or 2 or higher), such as Figure 5 As shown in (c), a second N-containing film of thickness T2 can be formed on the first N-containing film. The above cycle is preferably repeated multiple times. That is, it is preferable that the thickness of the second layer formed in each cycle is thinner than the desired film thickness, and the above cycle is repeated multiple times until the thickness of the second N-containing film formed by stacking the second layer reaches the specified thickness T2.

[0180] (Step A3)

[0181] After step A2 is completed, a removal agent is supplied to the wafer 200 in the processing chamber 201 through the same processing steps as step A2b described above.

[0182] By supplying a removal agent to the wafer 200 under the processing conditions described later, such as Figure 5 As shown in (d), it is capable of removing or neutralizing at least one of the inhibitor layer remaining on the oxide film surface. Figure 5 (d) in the figure shows the case where the inhibitor layer remaining on the surface of the oxide film is removed.

[0183] Then, the supply of the remover is stopped. Additionally, the treatment chamber 201 is purged using the same procedure as in step B of the above method.

[0184] Examples of processing conditions for supplying the removal agent in step A3 include:

[0185] Processing temperature: 200–1000℃, preferably 400–700℃

[0186] Processing pressure: 1~120000Pa

[0187] Processing time: 1–18000 seconds

[0188] Remover supply flow rate: 0-50 slm

[0189] RF power: 0~10000W.

[0190] It should be noted that RF power refers to the power applied to generate plasma in the case of plasma treatment using a remover. Furthermore, remover supply flow rate 0slm indicates the case where no remover is supplied. That is, it is also possible to remove at least one of the following: removing inhibitor layers remaining on the oxide film surface and neutralizing them, for example, by using heat energy generated from heating.

[0191] As a removal agent, substances containing oxygen (O) such as oxygen (O2), ozone (O3), H2O, hydrogen peroxide (H2O2), hydrogen (H2) + O2, H2 + O3, deuterium (D2) + O2, D2 + O3, nitrous oxide (N2O), nitric oxide (NO), nitrogen dioxide (NO2), carbon dioxide (CO2), and carbon monoxide (CO) can be used; substances containing nitrogen (N) and hydrogen (H) such as NH3, N2H2, and N2H4; reducing substances such as H2 and D2; inactive gases such as He, Ar, and N2; and mixtures thereof can be used.

[0192] It should be noted that the use of "H2+O2" as a combined term in this specification refers to a mixture of H2 and O2. When supplying a mixture, the two substances can be mixed (premixed) in the supply pipe before being supplied to the processing chamber 201, or the two substances can be supplied to the processing chamber 201 separately from different supply pipes and mixed (postmixed) in the processing chamber 201.

[0193] The above steps complete step A of this variation. Steps B and C, as described above, can then be performed.

[0194] In this modified example, the same effect as described above can also be obtained. Furthermore, according to this modified example, by performing steps A1 and A2, a second N-containing film of thickness T2 can be selectively formed on the first N-containing film of thickness T1 pre-formed on the surface of the substrate. Thus, a wafer 200 having an N-containing film and an oxide film formed on its surface at a thickness T2 that is thicker than the originally required thickness T1 can be efficiently prepared.

[0195] Furthermore, according to this modified example, after performing steps A1 and A2, step A3 is performed to remove or neutralize at least one of the inhibitor layer remaining on the oxide film surface. This prevents the etching of the oxide film in step B from being hindered by the inhibitor layer remaining on the oxide film surface. As a result, the etching of the oxide film in step B can be started smoothly and performed efficiently.

[0196] It should be noted that, Figure 5 (d) in the diagram illustrates the case where the inhibitor layer remaining on the oxide film surface is completely removed in step A3. However, after step A2, if the inhibitory effect of the inhibitor layer is sufficiently reduced or ineffective, it is not necessarily necessary to completely remove the inhibitor layer in step A3. Furthermore, after step A2, if there is no residual inhibitor layer on the oxide film surface, or if the inhibitory effect of the residual inhibitor layer on the oxide film surface is sufficiently reduced or ineffective, step A3 can be omitted.

[0197] That is, in this modified example, step B can also be performed while the inhibitor adsorbed on the surface of the oxide film in step A1 remains. In this case, the inhibitor remaining on the oxide film surface is removed along with the oxide film when the oxide film is etched in step B. Thus, by minimizing the amount of inhibitor layer removed, or omitting the removal of the inhibitor layer, the time required for inhibitor layer removal can be shortened or eliminated, thereby improving the productivity of substrate processing.

[0198] Furthermore, in step A2 of this modified example, the processing conditions can be appropriately selected so that the etching resistance of the second N-containing film to F-containing substances is lower than that of the first N-containing film to F-containing substances. For example, the processing temperature for forming the second N-containing film can be set lower than the processing temperature for forming the first N-containing film. This allows the second N-containing film to have lower purity and lower density than the first N-containing film. That is, the second N-containing film can be a film with more impurities and lower density. As a result, the etching resistance of the second N-containing film to F-containing substances can be lower than that of the first N-containing film to F-containing substances.

[0199] Furthermore, in step A2 of this modified example, the processing steps in step A2 can be arranged such that the etch resistance of the first N-containing film at least the portion in contact with the second N-containing film to F-containing substances is higher than that of the second N-containing film to F-containing substances. For example, before forming the second N-containing film, the pre-formed first N-containing film can be subjected to heat treatment (thermal nitriding, annealing, etc.) or plasma treatment (plasma nitriding, etc.). This allows the first N-containing film to achieve higher purity, higher density (densification), and harder surfaces compared to the second N-containing film. As a result, the etch resistance of the first N-containing film at least the portion in contact with the second N-containing film to F-containing substances is higher than that of the second N-containing film, thus imparting the surface of the first N-containing film with the function of an etch barrier layer. Alternatively, for example, an etch barrier layer with higher etch resistance than the first N-containing film can be formed on the pre-formed first N-containing film before forming the second N-containing film. It should be noted that the formation of the etch barrier layer, when accompanied by heat treatment or plasma treatment, can also be described as either heat treatment or plasma treatment of the first N-containing film.

[0200] By means of at least one of the above, in step B, over-etching of the N-containing film can be suppressed, and the portion of thickness T2 in the N-containing film can be removed with high precision while leaving the portion of thickness T1 remaining.

[0201] It should be noted that the processing conditions for heat treatment or plasma treatment of the first N-containing film in step A2 can be exemplified as follows:

[0202] Processing temperature: room temperature (25℃) to 800℃, preferably 300 to 700℃

[0203] Processing pressure: 1–5000 Pa, preferably 1–3000 Pa

[0204] Processing time: 1–300 seconds, preferably 1–200 seconds

[0205] Reactant supply flow rate: 0–20 slm, preferably 0.01–10 slm

[0206] Inactive gas supply flow rate: 0–20 slm

[0207] RF power: 0~10000W.

[0208] As reactants, substances similar to the various nitriding agents exemplified above can be used.

[0209] (Variation Example 2)

[0210] In step A, a laminated film of a first N-containing film of thickness T1 and a second N-containing film of thickness T2 may also be formed on the surface of the wafer 200 where no N-containing film has been formed. In this case, in step A, similar to modified example 1, step A1 of supplying a modifier to the wafer 200 and step A2 of supplying a second film-forming agent to the wafer 200 can be performed.

[0211] The following is mainly based on Figure 6 (a) in Figure 6 (d) in the text explains step A of this variation.

[0212] First, the wafer 200 to be processed is prepared in the processing chamber 201 through the same processing steps as described above for wafer filling and crystal boat loading. For example... Figure 6 As shown in (a) of this modified example, an oxide film is pre-formed on the surface of the wafer 200, and neither the first nor the second N-containing film is formed. The surface of the wafer 200 is partially exposed, and hereafter, this partially exposed surface of the wafer 200 will be referred to as the exposed surface of the wafer 200.

[0213] (Step A1)

[0214] After temperature and pressure regulation are completed within the processing chamber 201, a modifier is supplied to the wafer 200 within the processing chamber 201 through the same processing steps and conditions as in step A1 of Modified Example 1. Thus, as... Figure 6 As shown in (b), the inhibitor contained in the modifier can be selectively adsorbed on the surface of the oxide film and the exposed surface of the wafer 200 to form an inhibitor layer.

[0215] After an inhibitor layer is formed on the surface of the oxide film, the supply of the modifier is stopped. Additionally, the treatment chamber 201 is purged using the same process as in step B of the above method.

[0216] (Step A2)

[0217] After step A1 is completed, as follows Figure 6 As shown in (c), a stacked film of a first N-containing film of thickness T1 and a second N-containing film of thickness T2 is formed on the exposed surface of the wafer 200.

[0218] The first and second N-containing films can be formed using the same processing steps and conditions as in step A2 of Modified Example 1. That is, by performing the cycles including steps A2a and A2b of Modified Example 1 a predetermined number of times (n1 times, where n1 is an integer of 1 or 2 or more), a first N-containing film of thickness T1 can be formed on the exposed surface of the wafer 200. Then, by performing this cycle a predetermined number of times (n2 times, where n2 is an integer of 1 or 2 or more), a second N-containing film of thickness T2 can be formed on the first N-containing film. Similar to Modified Example 1, these cycles are preferably repeated multiple times.

[0219] (Step A3)

[0220] After step A2 is completed, a removal agent is supplied to the wafer 200 in the processing chamber 201 through the same processing steps as step A3 in modified example 1. Thus, as... Figure 6 As shown in (d), it is capable of removing or neutralizing at least one of the inhibitor layer remaining on the oxide film surface. Figure 6 (d) in the figure shows the case where the inhibitor layer remaining on the surface of the oxide film is removed.

[0221] Through the above process, step A of this variation is completed. Afterwards, steps B and C, as described above, can be performed.

[0222] In this modified example, the same effect as described above and in Modified Example 1 can also be obtained. Furthermore, according to this modified example, by performing steps A1 and A2, an N-containing film comprising a first N-containing film of thickness T1 and a second N-containing film of thickness T2 can be selectively formed on the exposed surface of the substrate. Thus, an N-containing film that is thicker than the originally required thickness T1 by a thickness T2 can be selectively formed (prepared) at a desired location on the substrate surface.

[0223] Furthermore, according to this modified example, similarly to modified example 1, step A3 is performed after steps A1 and A2. Therefore, the etching of the oxide film in step B can be started smoothly and performed efficiently.

[0224] It should be noted that, similar to Modified Example 1, after step A2, the amount of inhibitor layer removed in step A3 can be set to a minimum, or step A3 can be omitted, depending on the situation. That is, step B can also be performed while the inhibitor adsorbed on the oxide film surface in step A1 remains. In this case, the productivity of substrate processing can be improved.

[0225] Furthermore, in step A2 of this modified example, the processing conditions can be appropriately selected to make the etching resistance of the first N-containing film to F-containing substances higher than that of the second N-containing film to F-containing substances. For example, the processing temperature for forming the first N-containing film can be higher than that for forming the second N-containing film. Specifically, for example, the processing temperature for forming the first N-containing film can be set to 630°C or higher and 700°C or lower, and the processing temperature for forming the second N-containing film can be set to 500°C or higher and 630°C or lower. As a result, compared with the second N-containing film, the first N-containing film can be made more pure, denser, and harder. That is, the first N-containing film can be made into a film with fewer impurities, higher density (density), and harder. As a result, the etching resistance of the first N-containing film to F-containing substances can be higher than that of the second N-containing film.

[0226] Furthermore, in step A2 of this modified example, the processing steps in step A2 can be arranged such that the etch resistance of the first N-containing film at least the portion in contact with the second N-containing film to F-containing substances becomes higher than that of the second N-containing film to F-containing substances. For example, after forming the first N-containing film and before forming the second N-containing film, the first N-containing film is subjected to heat treatment (thermal nitriding, annealing, etc.) or plasma treatment (plasma nitriding, etc.) under the same processing conditions as shown in Modified Example 1. As a result, compared with the second N-containing film, at least the surface of the first N-containing film can be made to have higher purity, higher density (densification), and harderness. Consequently, the etch resistance of the first N-containing film at least the portion in contact with the second N-containing film to F-containing substances can be made higher than that of the second N-containing film to F-containing substances, thus endowing the surface of the first N-containing film with the function of an etch barrier layer. Alternatively, for example, an etch barrier layer with higher etch resistance than the first N-containing film can be formed on the first N-containing film before forming the second N-containing film. It should be noted that the formation of the etch barrier layer, when accompanied by heat treatment or plasma treatment, can also be described as either heat treatment or plasma treatment of the first N-containing film.

[0227] By means of at least one of the above, in step B, over-etching of the N-containing film can be suppressed, and the portion of thickness T2 in the N-containing film can be removed with high precision while leaving the portion of thickness T1 remaining.

[0228] (Variation Example 3)

[0229] In step B, the supply conditions of the F-containing material, i.e. the processing conditions when supplying the F-containing material to the wafer 200, can also be changed in multiple stages, such as two stages.

[0230] For example, in step B, the supply flow rate of the F-containing substance to the wafer 200, the supply flow rate of the inert gas, the concentration (partial pressure) of the F-containing substance, and the dilution rate of the F-containing substance can be changed in multiple stages. For example, in the latter half or final stage of step B, the supply flow rate of the F-containing substance can be lower than the supply flow rate of the F-containing substance before that stage. Additionally, for example, in the latter half or final stage of step B, the supply flow rate of the inert gas can be higher than the supply flow rate of the inert gas before that stage. Furthermore, for example, in the latter half or final stage of step B, the dilution rate of the F-containing substance can be higher than the dilution rate before that stage, thereby lowering the concentration (partial pressure) of the F-containing substance compared to its previous concentration (partial pressure).

[0231] For example, by setting the supply flow rate of the inert gas in step B to a predetermined flow rate of 0.5 slm to 10 slm, any of the above-mentioned effects can be achieved by lowering the supply flow rate of the F-containing substance in the latter half or final stage of step B compared to the supply flow rate of the F-containing substance in the preceding stages. Alternatively, by setting the supply flow rate of the F-containing substance in step B to a predetermined flow rate of 0.5 slm to 3 slm, any of the above-mentioned effects can be achieved by highering the supply flow rate of the inert gas in the latter half or final stage of step B compared to the supply flow rate of the inert gas in the preceding stages. Furthermore, by lowering the supply flow rate of the F-containing substance in the latter half or final stage of step B compared to the supply flow rate of the F-containing substance in the preceding stages, and highering the supply flow rate of the inert gas in the latter half or final stage of step B compared to the supply flow rate of the inert gas in the preceding stages, any of the above-mentioned effects can be achieved.

[0232] In this modified example, the same effect as described above can also be obtained. Furthermore, according to this modified example, in the latter half or final stage of step B, the reactivity between the F-containing material and the N-containing film can be reduced compared to previous reactivity, resulting in a lower etching rate than before. That is, according to this modified example, in step B, the reactivity between the F-containing material and the N-containing film can be reduced in multiple stages, and the etching rate can be reduced in multiple stages. This suppresses over-etching of the N-containing film, allowing for the precise removal of the portion of thickness T2 from the N-containing film while leaving the portion of thickness T1 remaining. It should be noted that, in this case, by pre-setting the etching resistance of the first N-containing film to the F-containing material to be higher than that of the second N-containing film, or by pre-setting the etching resistance of the first N-containing film at least at the portion in contact with the second N-containing film to the F-containing material to be higher than that of the second N-containing film, the removal of the portion of thickness T2 from the N-containing film while leaving the portion of thickness T1 remaining can be performed with even higher precision.

[0233] <Other aspects of the invention>

[0234] The foregoing has specifically described the methods of the present invention. However, the present invention is not limited to the methods described above, and various modifications can be made without departing from its spirit.

[0235] For example, in step B of the above method, the F-containing gas can also be supplied to the processing chamber intermittently, i.e., in a pulsed manner. For example, the supply of F-containing gas to the processing chamber and the purging and / or vacuum exhaust of the processing chamber can be alternated a predetermined number of times (m times, where m is an integer of 1 or 2 or more). In this case, the same effect as the above method can be obtained. In addition, according to this method, the reaction is reset by temporarily removing the reaction products and residual gas from the processing chamber during etching, thereby suppressing the generation of excessive etching reaction and improving the controllability of the etching amount.

[0236] Alternatively, for example, in step C of the above method, the first material can be supplied to the processing chamber intermittently, i.e., in a pulsed manner. For example, the supply of the first material to the processing chamber and the purging and / or vacuum exhaust of the processing chamber can be alternated a predetermined number of times (p times, where p is an integer of 1 or 2 or more). In this case, the same effect as the above method can be obtained.

[0237] Additionally, for example, in step C of the above method, a dopant can be supplied as a first film-forming agent in addition to the first raw material to the substrate. The dopant can be supplied from the dopant supply system described above. As a dopant, a substance containing any element from Group 15 such as phosphorus (P) and arsenic (As) and Group 13 such as boron (B) can be used. As a dopant, for example, phosphine (PH3), arsine (AsH3), diborane (B2H6), trichloroborane (BCl3), etc., can be used. One or more of these can be used as a dopant. In this method, the same effect as the above method can also be obtained. In addition, according to this method, a film doped with a dopant (P, As, B, etc.) can be formed on the substrate.

[0238] Alternatively, for example, in step C of the above method, a substance containing semiconductor elements other than Si can be used as the first raw material to form a film containing semiconductor elements other than a Si film on the substrate. For example, a Ge-containing substance such as monogermanane (GeH4) can be used as the first raw material to form a Ge film or similar Ge film on the substrate. Alternatively, for example, a Si-containing substance and a Ge-containing substance can be used as the first raw material to form a SiGe film or similar Si-containing film on the substrate. Alternatively, for example, in addition to the semiconductor element-containing substance as the first raw material, a nitriding agent and an oxidizing agent can be used to form films containing semiconductor elements and N such as SiN film, SiCN film, SiON film, SiOCN film, SiBCN film, and SiBN film, as well as films containing semiconductor elements and O such as SiO film and SiOC film on the substrate. Alternatively, for example, a substance containing metal elements can be used as the first raw material to form a W film, Mo film, Ru film, or similar metal element-containing film on the substrate. Alternatively, for example, in addition to the metal-containing substance as the first raw material, nitriding agents and oxidizing agents can also be used to form films containing metal elements and nitrogen, such as TiN films, WN films, and AlN films, as well as films containing metal elements and oxygen, such as TiO films, HfO films, ZrO films, and AlO films. In these cases, the same effect as described above can be obtained.

[0239] Alternatively, for example, in step C of the above method, epitaxial films, amorphous films, polycrystalline films, and mixed-crystal films thereof can also be formed on the substrate. For example, epitaxial Si films, amorphous Si films, polycrystalline silicon films, and mixed-crystal Si films of amorphous and polycrystalline silicon can also be formed on the substrate. In these cases, the same effect as the above method can be obtained.

[0240] Additionally, for example, in this invention, such as Figure 7 (a) in Figure 7 As shown in (f) in the diagram, it can also be performed as follows:

[0241] (a) Step A: preparing a substrate having a first substrate and a second substrate on its surface, wherein an oxide film is formed on the surface of the first substrate and an N-containing film is formed on the surface of the second substrate; and

[0242] (b) Step B, which involves etching an oxide film on the substrate surface by supplying an F-containing substance to the substrate and using a substance X generated by chemically reacting an N-containing film with the F-containing substance.

[0243] Additionally, in this case, in step A, as Figure 8 (a) in Figure 8 As shown in (d) above, it can also be done as follows:

[0244] (a1) Step A1, in which a modifier is supplied to a substrate, causing the inhibitor contained in the modifier to be adsorbed onto the surface of the oxide film;

[0245] (a2) Step A2, which forms an N-containing film on the surface of a second substrate by supplying a second film-forming agent to a substrate on which an inhibitor is adsorbed on the surface of an oxide film.

[0246] Figure 7 (a) in Figure 7 (f) in Figure 8 (a) in Figure 8 The methods shown in (d) are respectively for... Figure 4 (a) in Figure 4 (f) in Figure 5 (a) in Figure 5 The methods shown in (d) are partial modifications. Specifically, Figure 7 (a) in Figure 7 (f) in Figure 8 (a) in Figure 8 (d) in the text refers to... Figure 4 (a) in Figure 4 (f) in Figure 5 (a) in Figure 5 In diagram (d), "substrate" is changed to "first substrate," "first N-containing film" is changed to "second substrate," and "second N-containing film" is changed to "N-containing film." Here, "second substrate" is composed of a non-N-containing material (non-nitride), such as a film containing semiconductor elements (Si film, Ge film, SiGe film, SiOC film, SiC film, etc.), or a film containing metal elements (W film, Mo film, Ru film, HfO film, ZrO film, AlO film, etc.). Other components are respectively... Figure 4 (a) in Figure 4 (f) in Figure 5 (a) in Figure 5 The methods shown in (d) are similarly constructed.

[0247] exist Figure 7 (a) in Figure 7 (f) in Figure 8 (a) in Figure 8 In each of the methods shown in (d), the same effect as the above method can also be obtained. That is, in step A, a substrate with an oxide film formed on the surface of the first substrate and an N-containing film formed on the surface of the second substrate is prepared instead of a substrate with an oxide film formed on the surface of the substrate and a second N-containing film formed on the surface of the first N-containing film. The same effect as the above method can also be obtained.

[0248] Additionally, for example, in step C of the above method, a predetermined film can also be selectively formed on any portion of the various surfaces exposed by step B. For example, in Figure 4 In (f) of the above, the film can be selectively formed on the surface of the substrate and the first N-containing film, or selectively formed on the surface of the first N-containing film. Additionally, for example, in... Figure 7 In (f), a film can be selectively formed on the surface of the first substrate and the second substrate, or selectively formed on the surface of the second substrate. In these cases, the same effect as described above can be obtained.

[0249] The process for each process is preferably prepared individually according to the processing content, and is pre-recorded and stored in the storage device 121c via an electrical communication line and an external storage device 123. Furthermore, when starting each process, the CPU 121a preferably selects an appropriate process from the multiple processes recorded and stored in the storage device 121c according to the processing content. This allows for the reproducibility of various processes within the processing device. Additionally, it reduces the operator's workload, enabling the rapid initiation of each process while avoiding operational errors.

[0250] The aforementioned process is not limited to the case of new fabrication; for example, it can also be prepared by modifying an existing process already installed in the processing device. In the case of process modification, the modified process can also be installed in the processing device via an electrical communication line and a recording medium containing the process. Alternatively, the input / output device 122 of an existing processing device can be operated to directly modify an existing process already installed in the processing device.

[0251] In the above-described method, an example of processing using a batch processing apparatus that processes multiple substrates at a time has been described. The present invention is not limited to the above-described method; for example, it can also be applied to cases where processing is performed using a monolithic processing apparatus that processes one or more substrates at a time. Furthermore, in the above-described method, an example of processing using a processing apparatus with a hot-wall type furnace has been described. The present invention is not limited to the above-described method; it can also be applied to cases where processing is performed using a processing apparatus with a cold-wall type furnace.

[0252] Furthermore, the above-described method illustrates an example of performing the above-described processing sequence within the same processing chamber (in-situ) of the same processing device. The present invention is not limited to the above-described method; for example, any step of the above-described processing sequence and any other step may be performed separately in different processing chambers (ex-situ) of different processing devices, or they may be performed separately in different processing chambers of the same processing device.

[0253] For example, such as Figure 9 As shown, the present invention can also be applied when using a processing system comprising multiple independent processing units (processing units 1 to 3), where each step is performed non-in-situ within a different processing chamber of each processing unit. For example, step A can be performed in the first processing unit, step B in the second processing unit, and step C in the third processing unit. Alternatively, step A can be performed in the first processing unit, and steps B and C can be performed in the second processing unit. Alternatively, steps A and B can be performed in the first processing unit, and step C can be performed in the second processing unit. In these cases, the first to third processing units are also referred to as the first to third processing sections. It should be noted that the processing system is also referred to as a processing unit.

[0254] Additionally, for example, such as Figure 10 As shown, the present invention can also be applied to a processing system using a cluster-type processing apparatus comprising multiple processing chambers (processing chambers 1 to 3) arranged around a transfer chamber, where each step is performed in different processing chambers within the same processing apparatus. For example, step A can be performed in processing chamber 1, step B in processing chamber 2, and step C in processing chamber 3. Alternatively, step A can be performed in processing chamber 1, and steps B and C in processing chamber 2. Alternatively, steps A and B can be performed in processing chamber 1, and step C in processing chamber 2. In these cases, processing chambers 1 to 3 are referred to as processing units 1 to 3, respectively. It should be noted that the above-described methods and variations can also be examples where processing units 1 to 3 are the same processing unit. It should also be noted that the processing system is referred to as a processing apparatus.

[0255] When using these processing devices (processing systems), each process can be performed with the same processing steps and conditions as described above and in the modified examples, achieving the same effects as described above and in the modified examples. Furthermore, when performing steps B and C of the above processing sequence in a different location, the film-forming agent can be avoided from being introduced into the etching chamber, and the F-containing substance can be avoided from being introduced into the film-forming chamber. Therefore, cross-contamination between the various processing chambers can be prevented, and the quality of the etching process and the film-forming process can be improved respectively.

[0256] The methods and variations described above can be used in appropriate combinations. The processing steps and conditions can, for example, be set to be the same as those in the methods and variations described above.

Claims

1. Processing methods, including: (a) A process of preparing a substrate, wherein the substrate has an oxide film on its surface and a nitrogen-containing film formed in such a way that it is thicker than the originally required thickness T1 by a thickness T2; (b) A process of etching the oxide film on the surface of the substrate by supplying a fluorine-containing substance to the substrate and using a substance X generated by chemically reacting the nitrogen-containing film with the fluorine-containing substance.

2. The processing method according to claim 1, wherein, The nitrogen-containing membrane contains silicon, and the fluorine-containing substance contains hydrogen.

3. The processing method according to claim 1 or 2, wherein, The nitrogen-containing membrane comprises a silicon nitride membrane, and the fluorine-containing substance comprises hydrogen fluoride.

4. The substrate processing method according to any one of claims 1 to 3, wherein, The substance X contains nitrogen and hydrogen.

5. The processing method according to any one of claims 1 to 4, wherein, The substance X is generated during the etching of the portion of the nitrogen-containing film with thickness T2 by the fluorine-containing substance.

6. The processing method according to any one of claims 1 to 5, wherein, The substance X is generated by the decomposition of reaction products produced during the etching of a portion of the nitrogen-containing film of thickness T2 by the fluorine-containing substance.

7. The processing method according to any one of claims 1 to 6, wherein, The oxide film comprises a silicon oxide film.

8. The processing method according to any one of claims 1 to 7, wherein, The oxide film includes at least one of natural oxide films and chemical oxide films.

9. The processing method according to any one of claims 1 to 8, wherein, Also includes: (c) A process of forming a film on the surface of the substrate after the oxide film has been etched by supplying a first film-forming agent to the substrate.

10. The processing method according to any one of claims 1 to 9, wherein, (a) includes: (a1) The step of supplying a modifier to the substrate, thereby causing the inhibitor contained in the modifier to adsorb onto the surface of the oxide film; and (a2) A process of forming a state in which a nitrogen-containing film comprising a laminated film is formed on the surface of the substrate by supplying a second film-forming agent to the substrate on which the inhibitor is adsorbed on the surface of the oxide film, wherein the laminated film is a laminate of a first nitrogen-containing film of thickness T1 and a second nitrogen-containing film of thickness T2.

11. The processing method according to claim 10, wherein, In (a2), the second nitrogen-containing film is formed on the first nitrogen-containing film pre-formed on the surface of the substrate.

12. The processing method according to claim 10, wherein, In (a2), the laminated film is formed on the surface of the substrate.

13. The processing method according to any one of claims 10 to 12, wherein, (b) is performed while the inhibitor adsorbed onto the surface of the oxide film by (a1) remains.

14. The processing method according to any one of claims 10 to 13, wherein, In (a), the nitrogen-containing film is prepared in such a way that the first nitrogen-containing film has higher etch resistance to the fluorine-containing material than the second nitrogen-containing film has.

15. The processing method according to any one of claims 10 to 14, wherein, In (a), the nitrogen-containing film is prepared in such a manner that the etch resistance of the first nitrogen-containing film at least at the portion in contact with the second nitrogen-containing film to the fluorine-containing material becomes higher than the etch resistance of the second nitrogen-containing film to the fluorine-containing material.

16. The processing method according to any one of claims 10 to 15, wherein, In (a), at least one of the following operations is performed: The processing temperature for forming the first nitrogen-containing film is higher than the processing temperature for forming the second nitrogen-containing film; and After the formation of the first nitrogen-containing membrane and before the formation of the second nitrogen-containing membrane, the first nitrogen-containing membrane is subjected to heat treatment or plasma treatment.

17. The processing method according to any one of claims 1 to 16, wherein, In the nitrogen-containing film, the portion with thickness T1 has higher etch resistance to the fluorine-containing material than the portion with thickness T2.

18. The processing method according to any one of claims 1 to 17, wherein, In the nitrogen-containing film, the portion of thickness T1 that is in contact with the portion of thickness T2 has a higher resistance to the fluorine-containing material than the portion of thickness T2.

19. The processing method according to any one of claims 1 to 18, wherein, In (b), the supply conditions of the fluorinated substance are changed in multiple stages.

20. The processing method according to claim 5 or 6, wherein, In (b), a portion of thickness T2 in the nitrogen-containing film is removed, while a portion of thickness T1 remains.

21. A method for manufacturing a semiconductor device, comprising: (a) A process of preparing a substrate, wherein the substrate has an oxide film on its surface and a nitrogen-containing film formed in such a way that it is thicker than the originally required thickness T1 by a thickness T2; (b) A process of etching the oxide film on the surface of the substrate by supplying a fluorine-containing substance to the substrate and using a substance X generated by chemically reacting the nitrogen-containing film with the fluorine-containing substance.

22. A processing apparatus, comprising: Apparatus for preparing substrates; A fluorine-containing material supply system for supplying fluorine-containing materials to a substrate; and The control unit is configured to control the substrate preparation device and the fluorine-containing material supply system to perform: (a) a substrate preparation process, wherein the substrate has an oxide film on its surface and a nitrogen-containing film formed in such a way that it is thicker than the originally required thickness T1 by a thickness T2; and (b) an etching process of the oxide film on the surface of the substrate by supplying the substrate with a fluorine-containing material, thereby using a substance X generated by chemically reacting the nitrogen-containing film with the fluorine-containing material.

23. A program that is executed by a processing device via a computer: (a) The step of preparing a substrate, wherein the substrate has an oxide film on its surface and a nitrogen-containing film formed in such a way that it is thicker than the originally required thickness T1 by a thickness T2; (b) The step of etching the oxide film on the surface of the substrate by supplying a fluorine-containing substance to the substrate and using a substance X generated by chemically reacting the nitrogen-containing film with the fluorine-containing substance.

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